Electric time switch



1933- 0. K; ELLINGER ET AL 1,929,578

ELECTRIC SW??? Filed Aug. 55 19:51 3 Sheets-Sheet 1 Oct. 10, 1933. Q ELUNGER 5 7 1,929,578

ELECTRIC TIME SWITCH Filed Aug. 5, 1931 3 Sheets-Sheet 2 Oct. 10, 1933.

0. K. ELLINGER ET AL ELECTRIC TIME swi'rcn- Filed Aug, 5, 1931 3 Sheets-Sheet 3 Patented Oct. 10, 1933 UNITED STATES PATENT OFFICE and Emil Schramm, many Pirna-Neundorf, Ger- Application August 5; 1931, Serial No. 555,338, and in Germany August 6, 1930 Applications have been filed in Germany August 6, 1930, and June 10, 1931.

The present invention relates to electric time switches, in which a vessel similar to and operating on the principle of a sand-glass is provided, rotating about a horizontal axis of rotation and containing a fluid or other flowing substance, which vessel, by being brought into a certain position by hand or mechanical means, may be made to close a circuit, this being however subsequently interrupted owing to action due to the further movement of the vessel mentioned.

In switches of types hitherto known, the forces induced by displacement of the flowing substances employed are rather small. It has been found that they are not large enough to release contacts under strong spring tension. Although larger forces may be induced by increasing the quantity of the'fiowing substance, no advantage has been taken hereof, as such switches would have to be made too large and bulky.

The object of the present invention is to provide a switch operating on the sand-glass principle, but to restrict the dimensions of the vessel containing the flowing substance and therefore also the quantity of the latter, to a minimum, nevertheless inducing forces making quick-break, reliable action of switches even under strong spring tension possible. In the present invention, this advantage has been attained as follows: When the sand-glass or similar device in the switch is turned by hand or by mechanical means, e.g. by means of an electromagnet ,etc., a weight is simultaneously lifted. The latter does not, however, remain at rest in this elevated position, but just as the sand-glass device gradually turns bwing to the displacing movement of its flowing contents, the weight, too, isgradually moved onward to a point in which it is nolonger supported, but is allowed to fall downward, thereby suitably actuating the switching mechanism and simultaneously reaching its starting position. i

The sand-glass device and the flowing substance contained therein are provided solely for the purpose of moving the weight mentioned a short way along the final part of thecurved guide. The force necessary.for releasing the contacts is induced by the impetus of the weight falling down a certain distance. A device such as mentioned may easily be provided within a relatively small space, and it has been found that there is no difficulty whatever in constructing push button time switches suitable for strong currents and easily fitting into thewell 10 Claims. (Cl. 200-43) known recessed boxes about mm in diam., an advantage not offered by the devices hitherto kn'own.

-In order to clearly understand the nature of the present invention, reference may be had to the accompanying drawings, in which several modifications of the invention are shown.

In Figs. 1 to 4, the first constructional modification is shown. Figs. 1 and 2 are two side views in the on and off position of the switch, Figs. 3 and 4 are top and back views.

Figure 5 is a side elevation of a modified form of the device with certain rotating parts removed.

Figure 6 is a similar view to Figure 5 but with the rotating parts shown.

Figure '7 is a rear view of the modified form of the device. v

Figure 8 is a detail elevation of the rotating parts removed from the rest of the device.

Figure 9 is a section on the line 9-9 of Figure 8.

Figure 10 is a detail view of a certain forked slide and push button as used in the modified form.

Figure 11 is a side elevation of a certain latch member used in the modification.

Figure 12 is a side elevation of a main circuit closer used in this modification.

Figure 13 shows details disclosing a certain ball guide or retainer in front and side elevations as used herein.

Figure 14 is a section on the line, l414 of Figure 7 with the rotary parts removed and showing the switch open.

Figure 15 is a view similar to Figure 14 but showing the switch almost'closed.

Figure 16 is a. view' similar to Figure 15 but showing the switch fully closed and latched.

Figure 17 is a detail elevation of certain parts of a second modification of .the invention.

- Figure 18 is an elevation of the complete rotary group as used in the second modification.

Figure 19 is a detail side elevation of certain parts as used in a third modification of the invention.

Figure 20 is an elevation of the parts shown in Figure'19 but at right. angles thereto.

The base 1 of the switch carries a frame 2, a rigid contact 3 and a movable contact 4, touching the former by means of the contact surface 4a. The casing 6 containing the ball '7 and the sleeve 8 supporting the sand-glass 9 are connected and combined to form a double rotary system rotating round an axle 5 supported by the frame 2. To the axle is fitted a toothed disc 10. Moveably attached to the frame 2 is a slide or bar 11 carrying a push-button atits outer end, and also carrying a rack 13 which, when moved toward the switch base 1 engages with the toothed disc 10, thereby turning the double rotary system supported on the axle 5. If moved backward, the rack is, by means of a spring 14, moved upward so that it no longer engages with the toothed disc 10 but may freely move backward.

Fixed to the frame 2 is further a curved sprin 15 slightly projecting into the circular path of the rotary system, thus retarding the movement of same before attaining the vertical position and preventing same from turning backward after the switch is brought into its on position. This spring 15 is circularly extended to form part 16 which again prevents the ball 7 from falling out of its casing 6. The far end of same is made to form a catch 17 locking the free end 417 of the movable contact 4 after the latter has been forced outward by the movement of the double rotary system. I

The casing 6 containing the ball '7 is, on both sides opposite the axle (Fig. 4) provided with slots 6a in order to allow clear passage of a quadrental guide 18. When the switch is operated, the ball '7, after having been supported by the spring 16 till the casing reaches approximately horizontal position, then rolling back on to the curved guide 18, on which it is pushed upward till the rotary system reaches an approximately vertical position as shown in Fig. 1. The end part 18a of the curved guide 18 is practically horizontal, so that when being slowly moved onward by the displacing action of the sandglass, the ball is not lifted any further.

The device described works as follows: By pressing the button 12, the rack 13 engages the toothed wheel 10 on the axle of the rotary system, thus turning the latter round to a position shown by Fig. 1, in which the rotary system forms an angle with regard to the perpendicular. Simultaneously, the spring 15 prevents backward motion of the rotary system. In the course of this turning movement covering an angle of about 170-175, the moveable contact 4 is pressed against the rigid contact 3 and locked in this position by the catch 17 on the spring 16. The circuit is now closed, the switch being in its on position. During the turning movement of the rotary system, the ball 7, after having been first supported by the spring 16, falls on to the curved guide 18 on which it is moved upward till it reaches its highest position on the end part 18a. As the fluid orflowing substance contained in the sand-glass or similar device 9 gradually flows from the higher part into the empty lower half, the centre of gravity of the system is displaced and the rotary system of the switch thereby gradually turned into the vertical position (Fig. 2) covering the angle 12 indicated. Simultaneously, the ball 7 is gradually brought to the extreme end of part 180. of the curved guide 18 situated at a suitable distance from the vertical line passing through the axis of rotation 5. As soon as all the liquid or flowing substance has passed into the lower half of the sand-glass, the ball or weight 7 falls down onto the spring 16, 1'7 locking the contact 4, 4a, and forces same down on account of its impetus and suddenly releasing the locking contrivance 16, 17, so that the 'is a pair of spaced pedestals 22.

spring contact 4, 4a, 4b is free to immediately jump back into. the off position (Fig. 2).

In the form of the invention shown in Figures 5 to 16 there is provided a front plate 23 and projecting rearwardly from this front plate A flat plate 20 extends between these pedestals and pivot screws 105 extend through the pedestals and engage the ends of this plate to mount the same rotatably between the pedestals. Extending through the plate adjacent one end is a sleeve 108 which is preferably screwed into the plate. A sand glass 109 is mounted in this sleeve and projects at both ends therethrough. Extending through the plate, adjacent its other end, is a tube 106 wherein is mounted a ball 10'? normally free to move from one end to the other of the tube. Lugs 21 project inwardly at each end of the tube from the wall thereof and serve to keep the ball from leaving the tube. For purposes presently to be explained, the middle part of the plate 20 is twisted at a slight angle to its ends and also slots 106a are formed in the outer side of the tube 106 in spaced relation to the respective ends. This structure forms a rotary system. which may be seen in its entirety in Figure 8.

Formed integrally with the front plate 23 is a pair of spaced legs 26 having suitable grooves on their confronting faces to receive the arms 25 of a forked operating member or slide 24 which is attached to the. push button 112 to move therewith. These arms straddle the central portion of the plate 20 and projecting from the body of the member between the arms is a lug 28, best shown in Figure 10, which lies in such position that when the button is pushed in, it engages the twisted portion of the plate and forces the plate to turn on its pivots. One arm of the slide carries a head 2511 which is engaged by one end of a coiled compression spring 27 mounted in a slidable groove in one of the legs ton to protracted position. It will be clearly seen from reference to Figure 10 that the part 28 is beveled at the 'end to work smoothly over the middle of the plate 20 and it is also to be noted that this part 28 overlies the middle of the plate 20 when the button is pushed in so that it limits the movement. of the plate.

Fixed to one of the legs 26 on the side thereof is a pair of spring contact strips 41a and 42a (Fig. 15) arranged to receive the terminal ends of the wires 41 and 42 (Fig. 14) of the circuit controlled by the switch. Secured by a pivot screw 31 to the corresponding side of the other leg 26 is a lever 32 the detail shape of which is best seen in Figure 12. The different positions of this lever are also well shown in Figures 14, 15 and 16. It will be seen that this lever has a short arm which extends, downwardly and rearwardly from the pivot 31 and is provided with a latch lip 33, the purpose of which will be presently explained. The lever also has a long arm extending upwardly and forwardly from the pivot 31 and having an upwardly and rearwardly extending neck provided with a head This spring urges the slide and push butclosed position of Figure 1:; in which a is latched closed, as will nowbe described. Re-

ferring now to Figures 11, 14, '15 and 16, it will be seen that on the leg 26 which carries the pivot 31 and on the same side as that pivot there is a pivot screw 29' located near the rear end of said leg. At 30 is an arcuate .latch member having at one end-a lateral plate or head 30a which lies flat against the side of the leg 26 and is provided with an opening 29a through which the pivot screw 29 passes so that this latch is pivoted to the leg 26. The arcuate portion of the latch extends-forwardly beneath the path of the lower end of the tube 106 in parallelism thereto. This arcuate portion is provided with a laterally extending lip 301) which, when the lever 32 is in the latching position, as shown in Figure 16, engages behind the lip 33 and thus latches the lever 32. The spring'27 which urges the slide forwardly also presses against the upper end of a flange 300 formed on the head a to extend across the rear end of the leg 26 and thus urges the latch position shown in Figure 16.

into latching position. A spring 40 has one end engaged over the screw 29, bears on the under side of the screw 31 and engages with its other end a' lug 32a formed on the lever 32, the spring 40 thus urging the lever 32 to the open switch position shown in Figure 14.

In order-to provide for quick closing of the contact 41a on the bridging head 35, the lever 32 has at the angle between the long arm and neck,-a pivot pin 36 whereon is pivoted an insulating lever of the bell crank type having a long arm 37, which normally lies along the neck portion of lever 32, and a short arm 38 which engages a boss 26a, projecting rearwardly from the plate 23, when the parts are in the In this part of the device the long arm 37 is pushed beneath the contact 41a as the lever 32 begins its closing movement as shown in Figure 15. At this time,

the short arm 38 just touches the boss 26a. This holds the contact 41a out of engagement with the bridging head 35 but, upon further movement of thelever 32, the insulating lever moves to the position shown in Figure 16 so that the contact 41a snaps down on the bridging head 35 and completes the circuit.

A guide118 has a flange 11817 by means of which it is secured to one of the members 22 in such position that the arcuate body of the guide lies in the path of the slots 106a.

In the operation of this form of the device, the push button 112 is pressed inwardly which actuates the lever 32 to close the switch and permit the latch 30 to hold the switch closed. At the same time the rotary oup is rotated so that the full end of the sand glass is turned upwardly to lie just in front of a perpendicular position. In this position the'ball 107 will lie on top of the guide 118 near'the end thereof. As the sand runs down to the lower end of the glass the tube 106 is brought to a perpendicular position, whereupon the ball 107 drops from the upper end down onto the latch 30 which is thus kicked free from the lever 32 and the spring 40 snaps the lever to open position A plunger 39 serves-to manually trip the latch when desired.

Figs. 17 and 18 are views of a third modification of the invention. The axle 43 carries the support 208 for the sand-glass 209. The weight 207 is provided with a bore and is moveably fitted on guide206 made of wire or the like, supported by means of arms 44. The inode 01' operation is similar to that already described.- As soon as the device is turned by a suitable mechanism, the weight 207 is moved along the curved guide 218 and lifted to a point situated at an angle of (1 from the perpendicular passing through the axis of rotation. From this point the weight, owing to the displacing action of the sand-glass, is gradually moved forward, covering the remaining 10 and finally falling down to its original position, simultaneously operating some mechanism that brings the switch back into its off position. It is possible to omit the curved guide 218 and to substitute a roller 45, the mo tion being so suddenly imparted to the weight that owing to centrifugal force it is forced outward and easily lifted up on the roller 45. Instead of being made of circular shape, the weight 207 may, of course, be made square or any other 7 be turned in a direction suitable for actuating the switch and closing the circuit. The lever is again first turned about 170, 2. small plate spring preventing it from falling backward into its starting position, 'In the same way as in the other modifications of the present invention, the action of a sand-glass device is employed to move the lever 49 and the weight 207, the mo- .tionbeing again imparted by the device 48. As

soon as the vertical position is reached or slightly passed, the lever 49 with weight 207 will swing downward into its original position, simultaneously actuating a suitable releasing contrivance.

It will be observed in each form that the weight member and its associated parts constitute an impact mechanism and that this impact mechanism moves between set and release positions. Also, the sand-glass or the like constitutes means associated with the impact mechanism for effecting retarded movement from set to release position of said impact mechanism.

It must be mentioned that with regard to details of construction, the invention shall not be confined to the modifications here described. The arrangement of all parts named is subject to alteration, and in place of a. sand-glass or .similar devices containing other liquids, such as 1. A delayed action switch including a contact making lever normally in open circuit-position,

manually operable means for moving said lever to closed circuit position, a latch engaging said lever when in closed circuit position to hold the lever ,releasably in said position, an impact.

mechanism movable between set and release positions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanismincluding a striker element arranged to strike and trip the latch to release-the lever upon movement of the the impact mechanism to release position, and

means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position 2. A delayed action switch inc.uding a con tact making lever normally in open circuit position, manually operable means for moving said lever to closed circuit position, a latch engaging said lever when in closed circuit position to hold the lever releasably in said position, an impact mechanism movable between set and release positions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanism including a striker element arranged to strike and trip the latch torelease the lever upon movement of the impact mechanism to release position, means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position, and a spring urging said lever to open circuit position.

3. A delayed action switch including a contact making lever normally in open circuit position, manually operable means for moving said lever to closed circuit position, a latch engaging said lever when in closed circuit position to hold the lever releasably in said position, an impact mechanism movable between set and release positions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanism including a guided weight element arranged to strike and trip the latch to release the lever upon movement of the impact mechanism to release position, and means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position.

4. A delayed action switch including a contact making lever normally in open circuit position, manually operable means for moving said lever to closed circuit position, a latch engaging said lever when in closed circuit position to hold the lever releasably in said position, an impact mechanism rotatable about a horizontal axis intermediate its ends between set and release po sitions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanism including a striker element arranged to strike and trip the latch to release the lever upon movement of the'impact mechanism to release position, means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position, and a spring urging said lever to open circuit position.

5. A delayed action switch including a contact making lever normally in open circuit position, manually operable means for moving said lever to closed circuit position, a latch engaging said lever when in closed circuit position to hold the lever releasably in said position, an impact mechanism movable between set and release positions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanism including a guided weight element arranged to strike and trip the latch to release the lever upon movement of the impact mechanism to release position, means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position, and manually operable means to release said latch independently of the action of said impact mechanism.

6. A delayed action switch including a contact making lever normally in open circuit position, manually operable means for moving said lever to closed circuit position, a latch engaging said lever when it closed circuit position to hold the lever releasably in said position, an impact mechanism rotatable about a horizontal axis intermediate its ends between set and release positions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanism including a guided weight element arranged to strike and trip the latch to release the lever upon movement of the impact mechanism to release position, means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position, a spring urging said lever to open circuit position, and manually operable means to release said latch independently of the action of said impact mechanism.

7. The switch of claim 3 characterized by the guided weight consisting of a ball and a tube for guiding the same and further characterized by means being provided to hold the ball in the upper end of the tube in set position.

8. The switch of claim 3 characterized by the guided weight consisting of ,a member slidable on a wire and further characterized by means being provided to hold the member at the upper end of the wire in set position.

9. A delayed action switch including a contact making lever normally in open circuit position, manually operable means for moving said lever to closed circuit position, a latch engaging said lever when in closed circuit position to hold the lever releasably insaid position, an impact mechanism rotatable about a horizontal axis intermediate its ends between set and release positions and movable to set position by said manually operable means simultaneously with the movement of the lever to closed circuit position, said impact mechanism including a striker element arranged to strike and trip the latch to release the lever upon movement of the impact mechanism to release position, said striker element consisting of a lever pivoted at one end and weighted at its free end, the free end being arranged to strike and trip the latch upon movement from set to release position, and means associated with the impact mechanism to effect retarded movement of the impact mechanism from set to release position.

v 10. The switch of claim 3 characterized by having the last mentioned means including a sand glass like device rigidly attached to the impact mechanism and arranged to move the impact mechanism from set to release position upon flow of sand from one end of the glass to the other.

EMIL SCHRAMM.

OTTO KURT ELLINGER. 

